I have ran mine 6 times this year and let me tell you the tires suck. They grip alright but I have 8500 miles on the car and the tires will be worn down to nothing in the next month.(pissed)
As for how competative the MS6 is....well it's not. The car might do better with a better driver, this is my first season racing and I can't even touch the Protege's. They run 2+ seconds faster than me all the time. Those Protege's just handle really good. The MS6 falls in the SCCA DS class. Mine is in the STU class because of the CAI, with the EVO's and STI's. Believe it or not I have a better chance of keeping up with the EVO's and STI's than I do with the Protege's. I'll get back to you and let you know how the car does after I get all my suspension parts and run some events.
I'd have to say the main problems are:
1. The MS6 handles great on the road but on a tight Auto-X course it likes to push a lot in the corners.
2. The clutch is a weak point, this has already been discussed, so to help save it I don't downshift back to 1st unless I have a 180 degree corner. This just kills the car when you come out of a 90 degree corner in 2nd at 1500 RPM with NO boost.